Echocardiography is the use of ultrasound in the investigation of the heart and great vessels and diagnosis of cardiovascular lesions, and in transesophageal echocardiography (TEE), the ultrasonic record is obtained from a miniaturized transducer swallowed by a patient to predetermined distances in the esophagus and stomach.
TEE is a popular diagnostic procedure which is being used at ever-increasing numbers of medical centers worldwide. The quality of the image obtained during this procedure is a critical factor in obtaining accurate diagnoses, and the most important factor in obtaining quality images continuously is the positioning of the ultrasound sensor or transducer.
The transducer is typically mounted at the tip of the endoscope which is inserted through the mouth of the patient into the esophagus. This transducer is connected to imaging electronics, which then displays internal images of the patient on a screen.
Positioning systems for endoscope ultrasound probes are known. For example, U.S. Pat. No. 5,181,514 to Solomon et al. discloses a motorized positioning system which provides for automated control of an ultrasound transducer device. In this device, a switch mechanism is manipulated to provide power to actuate a motor which is mechanically coupled to the device. The device may be rotated to any angular position to provide a variety of scan planes for obtaining a plurality of corresponding two-dimensional cross-sectional images.
Methods for guiding medical equipment within the body are also known. For example, U.S. Pat. No. 5,445,144 to Wodicka et al. discloses an apparatus and method for acoustically guiding a distal end of a tube within a body. The method utilizes sound pulses reflected from within the body to guide insertion of the tube within the body.
To obtain a desired internal view with the transducer, the technician or clinician adjusts the endoscope while watching the screen. The technician may adjust the endoscope either by altering the depth of its insertion, rotating it, or tilting it until the desired view appears on the screen. The position of the patient is occasionally changed during the course of procedure such as TEE. As a result, the position of the endoscope changes, and this requires the technician to constantly adjust the endoscope to maintain an optimal view of the procedure. Therefore, the technician must constantly monitor the image on the screen in addition to performing other duties in the operating room or in the clinic.
A need therefore exists in the art for a system which will automate or simplify the task of obtaining a desired internal view of the patient and maintaining this view during positional changes of the patient.